http://www.ipa.go.jp/security/rfc/RFC2104JA.html
/*
** Function: hmac_md5
*/

void
hmac_md5(text, text_len, key, key_len, digest)
unsigned char*  text;                /* pointer to data stream */
int             text_len;            /* length of data stream */
unsigned char*  key;                 /* pointer to authentication key */
int             key_len;             /* length of authentication key */
caddr_t         digest;              /* caller digest to be filled in */

{
        MD5_CTX context;
        unsigned char k_ipad[65];    /* inner padding -
                                      * key XORd with ipad
                                      */
        unsigned char k_opad[65];    /* outer padding -
                                      * key XORd with opad
                                      */
        unsigned char tk[16];
        int i;
        /* if key is longer than 64 bytes reset it to key=MD5(key) */
        if (key_len > 64) {

                MD5_CTX      tctx;

                MD5Init(&tctx);
                MD5Update(&tctx, key, key_len);
                MD5Final(tk, &tctx);

                key = tk;
                key_len = 16;
        }

        /*
         * the HMAC_MD5 transform looks like:
         *
         * MD5(K XOR opad, MD5(K XOR ipad, text))
         *
         * where K is an n byte key
         * ipad is the byte 0x36 repeated 64 times
         * opad is the byte 0x5c repeated 64 times
         * and text is the data being protected
         */

        /* start out by storing key in pads */
        bzero( k_ipad, sizeof k_ipad);
        bzero( k_opad, sizeof k_opad);
        bcopy( key, k_ipad, key_len);
        bcopy( key, k_opad, key_len);

        /* XOR key with ipad and opad values */
        for (i=0; i<64; i++) {
                k_ipad[i] ^= 0x36;
                k_opad[i] ^= 0x5c;
        }
        /*
         * perform inner MD5
         */
        MD5Init(&context);                   /* init context for 1st
                                              * pass */
        MD5Update(&context, k_ipad, 64)      /* start with inner pad */
        MD5Update(&context, text, text_len); /* then text of datagram */
        MD5Final(digest, &context);          /* finish up 1st pass */
        /*
         * perform outer MD5
         */
        MD5Init(&context);                   /* init context for 2nd
                                              * pass */
        MD5Update(&context, k_opad, 64);     /* start with outer pad */
        MD5Update(&context, digest, 16);     /* then results of 1st
                                              * hash */
        MD5Final(digest, &context);          /* finish up 2nd pass */
}




/* crypto/hmac/hmac.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 * 
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 * 
 * Copyright remains Eric Youngfs, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from 
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/hmac.h>

void HMAC_Init(HMAC_CTX *ctx, const void *key, int len,
         const EVP_MD *md)
  {
  int i,j,reset=0;
  unsigned char pad[HMAC_MAX_MD_CBLOCK];

  if (md != NULL)
    {
    reset=1;
    ctx->md=md;
    }
  else
    md=ctx->md;

  if (key != NULL)
    {
    reset=1;
    j=EVP_MD_block_size(md);
    if (j < len)
      {
      EVP_DigestInit(&ctx->md_ctx,md);
      EVP_DigestUpdate(&ctx->md_ctx,key,len);
      EVP_DigestFinal(&(ctx->md_ctx),ctx->key,
        &ctx->key_length);
      }
    else
      {
      memcpy(ctx->key,key,len);
      ctx->key_length=len;
      }
    if(ctx->key_length != HMAC_MAX_MD_CBLOCK)
      memset(&ctx->key[ctx->key_length], 0,
        HMAC_MAX_MD_CBLOCK - ctx->key_length);
    }

  if (reset)  
    {
    for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
      pad[i]=0x36^ctx->key[i];
    EVP_DigestInit(&ctx->i_ctx,md);
    EVP_DigestUpdate(&ctx->i_ctx,pad,EVP_MD_block_size(md));

    for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
      pad[i]=0x5c^ctx->key[i];
    EVP_DigestInit(&ctx->o_ctx,md);
    EVP_DigestUpdate(&ctx->o_ctx,pad,EVP_MD_block_size(md));
    }

  memcpy(&ctx->md_ctx,&ctx->i_ctx,sizeof(ctx->i_ctx));
  }

void HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, int len)
  {
  EVP_DigestUpdate(&(ctx->md_ctx),data,len);
  }

void HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len)
  {
  int j;
  unsigned int i;
  unsigned char buf[EVP_MAX_MD_SIZE];

  j=EVP_MD_block_size(ctx->md);

  EVP_DigestFinal(&(ctx->md_ctx),buf,&i);
  memcpy(&(ctx->md_ctx),&(ctx->o_ctx),sizeof(ctx->o_ctx));
  EVP_DigestUpdate(&(ctx->md_ctx),buf,i);
  EVP_DigestFinal(&(ctx->md_ctx),md,len);
  }

void HMAC_cleanup(HMAC_CTX *ctx)
  {
  memset(ctx,0,sizeof(HMAC_CTX));
  }

unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len,
        const unsigned char *d, int n, unsigned char *md,
        unsigned int *md_len)
  {
  HMAC_CTX c;
  static unsigned char m[EVP_MAX_MD_SIZE];

  if (md == NULL) md=m;
  HMAC_Init(&c,key,key_len,evp_md);
  HMAC_Update(&c,d,n);
  HMAC_Final(&c,md,md_len);
  HMAC_cleanup(&c);
  return(md);
  }

SEO [PR] ”š‘¬!–³—¿ƒuƒƒO –³—¿ƒz[ƒ€ƒy[ƒWŠJÝ –³—¿ƒ‰ƒCƒu•ú‘—